Mounting for internal-combustion-engine pistons



g 13, 1 P. F. HACKEITHAL 3 HOUNTENG' FOR INTERNAL COMBUSTION ENGINE PIsTONS Filed Feb. 29, 1.923

Patented Aug. 13, 1929.

UNITED STATES PATENTOFFICE.

PA'UIi F. HAGKETHAL, OF CLEVELAND, OHIO,-,ASSIGNORTO RALPH L. SKINNER, OF

' DETROIT, MICHIGAN.

Mounzrme m InrnanAn-conaus'rron-nnemn rrs'rons.

Application filed February 29, 1928. Serial No. 257,919.

The object of the present invention is to provide simple means for use with the pistons of internal-cornbustion eng nes, or the like, whereby to eliminate ob]ect1onable,

5 audible, slapping or tapping noises due to the pistons coming into hammering or knocking contact with the walls of their cylinders, certain clearances between such pistons and their cylinders being necessary, especially 1n those instances where aluminum or alloy pistons are employed in cylinders of different metals, to allow or'compensate for the different heat coefficients of the pistons and the cylinder walls.

An additional purpose of the invention is to avoid the relatively-costly, close limits or tolerances now necessarily used between the pistons and their cylinder walls in an attempt to use engines, of the type referredto, which will not have the annoying piston slaps mentioned.

A further aim of the invention is to reduce the friction losses of v such reciprocating pistons, especially at their higher speeds of operations It has, heretofore, been proposed to overcome such piston noises or slaps by employat one end to the lower or the piston, and at its other end to the adjacent'part of the connecting-rod, with the object of holding the piston at all times against one side only of the cylinder in which the piston reciprocates.

Such a construction, for pistons of the usual diameter and with explosion gas pressures now commonly employed, would require a spring of such force or capacity that its size would preclude its employment in the 40 specified relation in the piston, using spring materials known today and with engines 0perated at the present-day high speeds.

' Furthermore, a spring which would be capable, regardless of its size and the space 5. available, of holding the piston continuously against one side only of the cylinder,

' would be of such great capacity that the friction produced thereby betweenthe piston and'the cylinder, for the complete engine 5 cycle, would be such a materially detrimental factor as would barits general, practical use J According to the principles of the present invention, one or more springsare employed in each piston, in such a way as to accomplish the above-stated and other objects without preventing the specified, rocking actions of the pistons into contact with the cylinder-walls, but cushioning such oscillatory movements of the pistons in their cylinders in such a manner as to avoid the occurrence of noisy slaps perceptible to the ear, and also reducing or lowering the piston to cylinder friction at the higher speeds of englne operation. T

To enable those acquainted with this art to understand the present invention fully, both from structural and functional standpoints, in the accompanying drawing, forming apart of this specification, and to which reference should be had in connection with the following, detailed description, a present, preferred embodiment of the invention has been illustrated, like reference characters referring to the same parts in the two views.

In this drawing,- Fig. 1 is a longitudinal section through one cylinder and piston, on substantially line 11 of Fig. 2, of a multi-cylinder engine; ing a coiled spring for each piston, attached skirt portion of and Fig. 2 is a cross-section on line of Fig. 1, the parts being viewed in thedn'ection indicated by the arrows.

Referring tothe views of this drawing,

, it will be noted that the hollow piston 10,

13 clamped inside a split, upper end of the connecting-rod, by a tightening screw 14, such pin being at, or slightly to one side of, the axis of the piston, as may be preferred.

So far as described, the construction is of the customary form now in common use.

The screw 14: also holds in place a doubleended clip 15, the terminal, downturned ears 16, 16 of which are apertured to receive the hook-shaped ends of a pair ofvcoiled springs 17, 17, the opposite ends of which hook into holes in small platesl18, 18 fastened to the lower'portion' of the piston-skirt on the side of the connecting-rod opposite the attach- .ment of the spring ends to the clip 15.

, As is clearly shown, the ears or lugs 16,

-' 16 and the plates or brackets 18, 18 are spaced apart sufiiciently to position or locate t e springs on opposite sides of the connecting-rod and out of contact or conflict therewith, the lower end of the connecting-rod being associated with the engine crank-shaft 19--in the usual way.

It is of obvious advantage to place the anchorage of the spring or springs atthe connecting-rod end as close as possible to the axis of the piston-pin to reduce the travel of that end of the spring, which is a function of'the angularity of the connecting-rod, thereby straining the spring or springs through such a small range as to insure length of operative, life thereof.

In the earlier proposed construction, where this attachment point is on the same side of the connecting-rod as the anchoring point tothe piston, a certain angle is obf tained between the axis of the spring and the vertical piston-wall corresponding to the point of attachment of the spring to the piston, but by securing the spring or springs.

when the forces acting on the piston thrust it from one side of its cylinder to the otherside, as when the pressure of the exploded gases issuddenly imposed on the top face of the piston to cause its descent, such pressure acting on the piston while its connecting-rod is at an oblique angle thereto.

It will be understood, therefore, that the spring means is-so designed and arranged as not to'prevent the rocking or oscillatory movements of the piston between the opposite side-walls of the cylinder, or, stated difi'erently, it does not maintain the piston sufiiciently rigidly with relation to its connecting-rod to constantly keep the contact of the piston at one side only of its cylinder, but, on the contrary, as the forces acting on the piston tending'to thrust or shift it 'into slapping or hammering contact with either side of the cylinder occur, the spring means will absorb, or cushion such movements of the piston sufiiciently to preclude the occurrence of annoying, audible slaps,

taps, or knocks.

Such desirable result is,- in all likelihood,

due to the checking or retardation of the speed with which the piston shifts its posit1on when the spring means is used in the indicated relation.

This avoidance of rapid, powerful, crosswise, p'iston-rocking movements in its cylinder, thus excludingthe slapping or hammering action referred to, results in reduced piston and cylinder wear.

The capacity or power of the sprin means employed depends upon a number 0 determining influences, such as the gas pressures on-the top of the piston, the shape of the combustion-chamber of the cylinder, the location of .the spark plug, the diameter of the piston, the weight of the reciprocating parts, the location of the piston-pin in the piston, the ignition timing, etc.

The spring means used to satisfactorily meet the conditions and to perform the functions hereinabove detailed is only a small part of the strength of a spring which would be needed to keep the piston always in' contact with one side only of the cylinder, and, accordingly, sufficient space is available inside of the piston to accommodate the spring means performing the peculiar and limited functions to accomplish the results outlined in the manner stated.

The spring means, in addition to avoiding.I

the occurrence of audible, piston slaps, also prevents piston-pin knocks or noises due to the necessary clearance between the pistonpin and its bearing, whether such bearing is in tire piston or in the connecting-rod, or in I (it Such highly desirable effect is brought about because the end of the spring or springs anchored to the connecting-rod holds t e pin and bearing in sidewise contact adequately to effect a sliding or rolling travel of the pin and bearing relative to one another in the curved path of one side of the bearing, thus removing substantial play of the in and bearing lengthwise the piston,

and ence avoiding such audible, piston-pinnoises.

u Furthermore, in some instances, there is a tendency for the piston-pin to oscillate more or less sidewise relative to its bearing, at certain speeds or periods of the engine, due to whipping of the connecting-rod, or, in other instances, especially at high engine speeds,

owing to the centrifugal action of the reciprocating masses which are under the influences of associated, revolving members, all of which actions, unless prevented, may produce objectionable noises, either by the piston-pin or the piston.

.Such distasteful, noisy occurrences are adequately and properly reduced by the employment ofthe spring means, which, under these circumstances, either maintains the sidewise contact of the piston-pin and hearing or sufliciently cushions the movements ill of the pin and bearing relative to one another, or cushions the motions of the piston in the: cylinder.

Those acquainted with this art will readily understand that the invention, as defined by the following'claims, is susceptible of a variety of satisfactory embodiments, and. is not limited to the single, particular embodiment presented. herein-in detail.

I claim:

L The combination of a cylinder, a piston Ieciprocatory therein, a crank-shaft, a connecting-rod rockingly mounted on said pis ton and crank-shaft, and a coiled spring anchored to said piston and to said connectingrod on the side of the latter opposite such attachment of the spring to the piston and of such capacity as to permit the transverse thrust movements of the piston in the cylinder and to cushion the same sufiiciently to substantially eliminate iston slaps audible 0 the unaided hearing 0? the average human elng.

2. The-combination of a cylinder, a piston having a piston-pin reciprocatory in said cylinder, a crank-shaft, a connecting-rod rockingly mounted on said crank-shaft, and rockingly associated with said piston through said'piston-pin, one ,of said elements having a bearing in which said piston-pin turns, and a coiled spring anchored to. said piston and to said connectlng-rod on the side -of the latter opposite such attachment of the spring tothe piston and of such capacity as to cushion the relative movements of said piston-pin and its bearing to eliminate noisy play therebetween audible to the unaided hearing of the average human being.

'3. The combination of a cylinder, a piston recipriocatory therein, a crankshaft, a

connecting-rod rockingly associated with said piston and crank-shaft, and a spring anchored to said piston and to said connectingrod on the side of the latter opposite such attachment of the spring to the piston, such spring crossing said connecting-rodand of such capacity as to permit the transverse thrust movements of the piston inthe cylinder and to cushion the samesuflicientl to substantiall eliminate piston slaps 'au ible "to the unai ed hearing of theaverage human being.

4. The combination of a cylinder, a piston havinga pistonin reciprocatory insaid cylinder, a man rockingly mounted on said crank-shaft and rockingly associated with said p ston through said piston-pin, one of said elements having a bearing in which said piston-pin piston and crankshaft, and a pair of springs anchored to said piston and to said connecting-rod on the side of the latter opposite such attachment of the springs to the ms 7 ton, the connecting-rod being located between said springs, such springs being of such capacity as to permit the transverse thrust movements of the piston in the cylinder and to cushion the same sufficiently to substantially eliminate piston slaps audible to the unaided hearing of the average human being.

6. The combination of a cylinder, a piston having a piston-pin reciprocatory in said cylinder, a crank-shaft, a connecting-rod rockingly mounted on said crank shaft and 'rockingly associated with said piston through said piston-pin,'one of said elements having a bearing in which said piston-pin 9 I turns, and a pair of springs anchored to said piston and to said connecting-rod on the side of the latter opposite such attachment of the springs to the piston, said connectingrod being located between said springs, such 5 springs being of such capacity as to cushlon.

therelative movements of said piston-pin and its bearing to eliminate noisy play therebetween. v

" In witness whereof I have hereunto set my hand.

PA L F. HAoKiiTHAL.

-shaft, a connecting-rod 55' 

